Amylin Pharmaceuticals and Takeda Enter into Worldwide Agreement to Co-Develop and Commercialize Compounds for Obesity

November 2, 2009

Amylin Pharmaceuticals, Inc. (Nasdaq: AMLN) and Takeda Pharmaceutical Company Limited (TSE: 4502) announced today that they have entered into a worldwide exclusive license, development and commercialization agreement to co-develop and commercialize pharmaceutical products for the treatment of obesity and related indications.The agreement includes products to be developed from Amylin’s pipeline, including pramlintide/metreleptin and davalintide, which are compounds currently in phase 2 development for treatment of obesity. The agreement also includes additional compounds from both companies’ obesity research programs. Amylin will receive a one-time up-front payment of $75 million from Takeda and, over the term of the agreement and in relation to the compounds under the agreement, is eligible to receive additional payments upon achieving certain development, commercialization and sales-based milestones that could exceed $1 billion. The agreement also provides for future tiered, double-digit royalty payments to Amylin based on global product sales.

Under the terms of the agreement, Amylin will be responsible for executing development activities for potential products through phase 2 with the aim of regulatory approval in the U.S. Takeda will lead development activities beyond phase 2 in the U.S., and all development activities outside the U.S. In most instances, Amylin will be responsible for 20% of development costs associated with obtaining approval for products in the U.S. and Takeda will be responsible for 80% of such U.S. development costs. Takeda will be responsible for 100% of development costs associated with obtaining approval for products outside the U.S.

Takeda will lead product commercialization, both in the U.S. and outside the U.S., and will be responsible for 100% of commercialization costs. Amylin will have the option to co-commercialize the first two approved products in the U.S. and any follow-on products containing the identical active ingredients.

“Takeda is excited to realize this partnership with Amylin focused on the treatment of obesity and related indications. By leveraging Takeda’s global development and commercial infrastructure we look forward to maximizing the significant potential of the products under this agreement,” said Yasuchika Hasegawa, president & chief executive officer, Takeda Pharmaceutical Company Limited. “Both Amylin and Takeda have extensive experience in the diabetes and metabolic disease area, and this collaboration should allow us to more quickly bring promising new treatments to patients in need."

“This collaboration will leverage Amylin’s experience and expertise with peptide and protein science and Takeda’s worldwide development and commercial expertise,” said Daniel M. Bradbury, president and chief executive officer, Amylin Pharmaceuticals. “Amylin recognizes the enormous potential of this collaboration to advance more options in obesity treatment more quickly than either company could do alone. Amylin and Takeda are excited about working together to address the significant unmet need for the millions of patients who need better solutions to manage obesity."

About Obesity

Obesity is rapidly becoming a major health problem in all industrialized nations and many developing countries. It has reached epidemic proportions globally, with more than 1 billion adults overweight, and at least 300 million of them obese. Obesity is a chronic disorder that is linked to increased health risk of several medical conditions including type 2 diabetes, non-alcoholic fatty liver disease, high blood pressure, heart disease, stroke, osteoarthritis, sleep disorders and several types of cancers. According to The Obesity Society, obesity is the second leading cause of preventable death in the United States. The total direct and indirect cost burden attributed to treating overweight and obesity and related conditions has grown to nearly $150 billion in the United States each year.

About Amylin Pharmaceuticals

Amylin Pharmaceuticals is a biopharmaceutical company dedicated to improving lives of patients through the discovery, development and commercialization of innovative medicines. Amylin has developed and gained approval for two first-in-class medicines for diabetes, SYMLIN® (pramlintide acetate) injection and BYETTA® (exenatide) injection. Amylin's research and development activities leverage the Company's expertise in metabolism to develop potential therapies to treat diabetes and obesity. Amylin is headquartered in San Diego, California. Further information on Amylin Pharmaceuticals is available at www.amylin.com.

About Takeda

Located in Osaka, Japan, Takeda is a research-based global company with its main focus on pharmaceuticals. As the largest pharmaceutical company in Japan and one of the global leaders of the industry, Takeda is committed to striving toward better health for individuals and progress in medicine by developing superior pharmaceutical products. Additional information about Takeda is available through its corporate website, www.takeda.com.

Forward-Looking Statements

This press release contains forward-looking statements about Takeda and Amylin, which involve risks and uncertainties. The actual results for each Company could differ materially from those discussed due to a number of risks and uncertainties, including that the obesity co-development and commercialization agreement mentioned in this press release will not achieve the results we expect; our clinical trials may not start when planned, be completed in a timely manner and/or confirm previous results; our preclinical studies may not be predictive; our product candidates, including those covered by the co-development and commercialization agreement mentioned in this press release, may not receive regulatory approval; and inherent scientific, regulatory and other risks in the drug development and commercialization process.

With respect to Amylin, these and additional risks and uncertainties are described more fully in Amylin’s most recently filed SEC documents, including its Form 10-Q. Amylin undertakes no duty to update these forward-looking statements.